…etInserts()` (#1070)

Also add `SyncInserts.GetRecords()` for parity with `WriteInserts`

`c.Type.ID()` is same for all Arrow extension types so instead of excluding the JSON type from list testdata, it excludes all extensions.

Brings the test from #986 (fix was included in #1064)

…1072)

This: 
 - adds an `id` field that is used as an auto-incrementing integer field in tests, and can be used to order records by so that tests can pass regardless of sort order returned by a plugin's Read method
 - makes null rows an explicit option (rather than every other row being null) and starts using null rows in tests again

// Apply applies the given transformers to the given Tables, and recursively on the relations.
// This is useful for applying transformers that are not defined in the table definitions. To apply the table-definition transformers, use TransformTables.

Shuffling missed a case (I think) because we were using the same seed every time. Iterating over the items in reverse should have the same effect and is still deterministic.

Same fix as in #1074 but also adds a test for it.

Follow-up for #1072 & #1002

This updates the ticker logic in the batch writers to reset the ticker when a flush happens. This is better, as it still guarantees that a message won't be delayed by more than batch_timeout, but we don't risk flushing a very small batch because we must flush at regular intervals either.

The choice of resetting _after_ the flush is deliberate: it means that the maximum amount of time between flushes is:

```
max_time = flush_time + batch_timeout
```

otherwise we could do:

```
max_time = batch_timeout
```

but if a flush were to then longer than the batch timeout, we can end up in a cycle of flushing again immediately after the previous flush finishes.

🤖 I have created a release *beep* *boop*
---


## [4.8.0-rc1](v4.7.1-rc1...v4.8.0-rc1) (2023-07-05)


### Features

* **transformers:** Add `Apply` to apply extra transformations ([#1069](#1069)) ([a40598e](a40598e))


### Bug Fixes

* Deterministic ordering for records returned by readAll in tests ([#1072](#1072)) ([cf7510f](cf7510f))
* Handle null-related test options ([#1074](#1074)) ([88f08ee](88f08ee))
* **naming:** Rename `SyncMessages.InsertMessage()` to `SyncMessages.GetInserts()` ([#1070](#1070)) ([ab9e768](ab9e768))
* Reset timers on flush ([#1076](#1076)) ([767327f](767327f))
* Reverse order of records in memdb ([#1075](#1075)) ([8356590](8356590))
* **scalar:** Test `AppendTime` on TimestampBuilder ([#1068](#1068)) ([888c9ee](888c9ee))
* **testdata:** Exclude only the correct type ([#1067](#1067)) ([1c72fb2](1c72fb2))

---
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